The present invention relates to an insulator assembly. More particularly, the present invention relates to an insulator assembly having a spacer for conducting electrical current from the terminal pad of a bypass switch assembly to the contact of a switch assembly.
Distribution reclosers are mounted to support structures in electrical power distribution systems to prevent longer than momentary disruptions of electrical service, such as might be caused by a short circuit, and to provide continuous electric service. For example, wind conditions often cause power lines strung between poles to swing, thereby momentarily touching each other or a grounded conductor. Additionally, objects may fall across exposed wires, arcing could occur, or other transitory events could cause momentary power line short circuits or current surges that could burn out a fuse or trip a circuit breaker. Most of these faults are self correcting and do not require permanent fuse or circuit breaker protection because they terminate quickly. Reclosers sense and interrupt fault currents and automatically restore service after momentary outages after the temporary fault condition is gone. If a fault is permanent, the recloser locks open after a preset number of operations and isolates the faulted section of the system from the main system.
Bypass switch assemblies may be used to provide an economical and practical method of bypassing current and disconnecting distribution reclosers to provide maintenance to the reclosers without interrupting electrical service. Once the recloser has been isolated from the electrical distribution system, maintenance may be performed on the recloser without impairing continuous electric power.
Insulator assemblies are spaced from the support structures to which they are attached, such as utility poles. The sizes of switches and conductors are based upon the current and basic insulation level requirements. The stiffness of a conductor increases as the diameter of the conductor increases. Stiffer conductors are less flexible, thereby preventing them from being easily formed to facilitate connecting with connectors on terminal pads and maintaining electrical clearance on grounded parts. Terminal pads for existing switch assemblies are flat, thereby requiring some forming of conductors to connect to bypass switch assemblies that are mounted near the support structure. Due to the stiffness of large conductors, difficulty exists in forming to the degree necessary to connect to the straight terminal pads of existing insulator assemblies that are mounted near the support structures. Therefore, it is difficult to connect large conductors to terminal pads of existing insulator assemblies that are mounted close to support structures due to the inflexibility of the conductor. A need exists for a terminal pad that allows conductors to be connected to insulator assemblies that are mounted near support structures.
Insulator assemblies are mounted to support structures using multi-piece mounting assemblies. Such multi-piece mounting assemblies are unwieldy as they require a technician to carry a number of different parts in the field. Moreover, installation is difficult and slow due to the number of parts that must be assembled. Therefore, a need exists for a mounting assembly for an insulator assembly that has few parts and is quick and easy to install.
Insulator assemblies are supported on base assemblies that are bolted together, which allow movement of the parts of the base assemblies over time. Such movement is due to many uncontrollable events, such as weather, animals, vandalism and the operation of the switches mounted on the base assemblies. Movement of the base assemblies causes the blade and contact of the insulator assemblies to move out of alignment, thereby effecting electricity transfer through the insulator assembly. Therefore, a need exists for a base assembly for an insulator assembly that is rigidly connected and is not prone to movement over time.
Elaborate shunting devices are needed to transfer electricity from the terminal pads to the contacts of switch assemblies of insulator assemblies when the bypass blades of bypass switch assemblies are in open positions, which is the normal operating position for bypass switch assemblies. The shunting devices are bulky and difficult to install. Therefore, a need exists for a bypass switch assembly that transfers electric current from the terminal pad of a bypass switch assembly to the contact of a switch assembly of an insulator assembly without a shunting device.
Therefore, a need exists for improved insulator assemblies.
Accordingly, it is an objective of the present invention to provide a spacer for transferring electrical current from terminal pads to the contacts of switch assemblies of insulator assemblies when the bypass blades of bypass switch assemblies are in open positions, thereby eliminating the need for an elaborate shunting mechanisms.
The foregoing objective is basically attained by providing an insulator assembly having a base. A first switch assembly is connected to the base and has a first switch blade movable between open and closed positions. A second switch assembly is connected to the base and has a second switch blade movable between open and closed positions. A bypass switch assembly is connected to the base and has a bypass switch blade movable between open and closed positions. The bypass switch assembly has a first conductor electrically connected to the bypass switch blade when the bypass switch blade is in the closed position. A support member is connected to the first conductor and has an opening. A second conductor is electrically connected to the first switch blade when the first switch blade is in the closed position. A spacer is disposed in the support member opening to transfer electrical current from the first conductor to the second conductor. The spacer has a first surface in electrical contact with the first conductor and has a second surface in electrical contact with the second conductor. The spacer provides a path for the electrical current from the terminal pad of the bypass switch assembly through the steel support member to a contact of a first switch blade of a first switch assembly, thereby eliminating the need for an elaborate shunting mechanism to provide a path for the electrical current around the steel support member.